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Posts tagged ‘Education’

Industry Steps up CO2 Training Efforts

         Don Gillis | Lead Technical Trainer

          Emerson’s Educational Services

The use of commercial CO2 refrigeration technology is expected to increase significantly over the next few years. But in the U.S., very few service technicians have experience installing, commissioning and maintaining CO2 systems. I recently contributed to an article in Contracting Business that discussed how our industry is addressing the urgent need for CO2-specific education, training and certification programs.

Compared to legacy hydrofluorocarbon (HFC) systems, CO2 (refrigerant name R-744) has many unique performance characteristics and system properties. Because CO2 refrigeration is still relatively new to the U.S. market, most HVACR trade schools and technical colleges simply haven’t integrated CO2 topics into their refrigeration training programs. But today, that’s quickly changing.

Stakeholders collaborate to develop CO2 curriculum

Original equipment manufacturers (OEMs) and industry organizations are actively trying to bridge this knowledge gap by developing CO2 training curricula and certification programs. As an industry steward of sustainable refrigeration and a provider of fully integrated CO2 solutions, Emerson is helping industry organizations to accelerate these efforts.

We’re collaborating with the North American Sustainable Refrigeration Council (NASRC), the ESCO Group and other industry stakeholders to spearhead the development of the first CO2 curriculum for community college and trade school HVACR programs in the U.S.

According to Morgan Smith, program and communications director at the NASRC, the goal of this collaboration is to integrate a CO2 curriculum into the commercial refrigeration tracks at technical colleges. The new curriculum will cover a wide range of topics to help familiarize technicians with CO2 refrigeration, including:

  • Basic terms and definitions of CO2 characteristics and systems
  • CO2 safety fundamentals, such as: handling, tools and gauges, relief requirements, leak rates and room sensors
  • Core curricula, including: required experience; understanding CO2 as a refrigerant; operating characteristics; types of CO2 systems; working with non-traditional system components, compressor types, control systems and equipment applications
  • Installation procedures: handling CO2 as a refrigerant; installation fundamentals and piping insulation
  • System commissioning procedures
  • Service and maintenance procedures, such as: system charging and discharging; repairing and replacing components; CO2 oil management; CO2 system recovery; defrost methods and custom systems
  • Troubleshooting

“Because CO2 is so new to the U.S. commercial refrigeration market, technicians and end users have varying degrees of hesitation. We hope these training programs will help remove some of the mystery and concerns about using this efficient and environmentally friendly natural refrigerant,” Smith said.

Emerson CO2 training programs

Emerson continues to expand on our CO2-specific training initiatives through our mobile training units and Educational Services programs. In 2019, we introduced our third-generation CO2 mobile training unit to serve Canada and the continental U.S.; to date, it has trained more than 1,000 industry professionals in North America.

This year, we’ll be launching a second CO2 mobile training unit at Emerson Educational Services’ primary location in Sidney, Ohio. Once there, it will become the centerpiece of a two-day training program designed to give contractors, OEMs, wholesalers and end users a hands-on experience of what it’s like to work on a CO2 transcritical booster refrigeration system. As COVID-related health guidelines permit, we hope to send our CO2 mobile training units back on the road to be featured at industry events and provide training where it is needed most.

In addition, Emerson Educational Services currently offers two virtual and in-person training courses related to CO2:

  • Two-day “CO2 Refrigeration” course specifically designed to train technicians
  • One-day course entitled, “Fit for the Future: Working with Natural Refrigerants, A2Ls, and A1 HFO Blends”

The net goal of all these efforts is to give the entire commercial refrigeration supply chain — from wholesalers and distributors to OEMs, end users and service technicians — a greater familiarity and comfort level with CO2 refrigeration. To learn more about the CO2 training programs at Emerson, visit our course schedule, or contact Emerson Educational Services at Education@Emerson.com.

 

STEM Day Brings Emerson’s Yearlong Efforts Into Focus

Ken Monnier | Chief Technology Officer,

Emerson’s Commercial and Residential Solution’s Business

November 8 is Science, Technology, Engineering, Art and Math (STEM/STEAM) Day — a time when the nation pauses to recognize the importance of these disciplines within our educational curricula. At Emerson, we are committed to supporting STEM initiatives year-round, and STEM Day allows us to reflect on the year’s activities and plan for what’s to come. In a historically male-dominated industry, it’s particularly important for Emerson to celebrate the contributions of women in our organization and create an environment where they can thrive and succeed. Let’s look at some of the ways we’re leveraging STEM initiatives to help create the next generation of engineers and support the increased inclusion of women within our industry.

Women in STEM (WiS) program charter and achievements

Emerson created its global WiS program to attract, develop and retain the top women candidates in STEM-related roles, enhance the diversity of ideas and approaches for the benefit of our customers, and fully deliver on our “Consider It Solved” promise. The program supports generations of women in all stages of their careers, from schoolchildren who are just beginning to think of their futures to professionals and senior executives who are navigating their career paths.

Based on some of the metrics gathered, we are well on our way to achieving the goals of this charter.

  • Membership increased to more than 5,000 global members
  • STEM-related webinar event attendance increased by 60%
  • Local chapter (Sidney, Ohio) membership increased by 10%
  • Launched a new global WiS SharePoint site
  • Ranked as #12 on Women Engineer Magazine’s list of top companies to work for
  • Awarded Gold, Best Practice Outreach and Best Practice Professional Partnerships by the Society of Women Engineers (SWE)

These achievements are indicative of the three guiding principles of our WiS program:

  1. Attract and inspire young girls to pursue STEM subjects and careers while recruiting top STEM female candidates to work at Emerson
  2. Provide opportunities to develop leadership skills and elevate the visibility for women in STEM-related roles
  3. Create an inclusive, connected community where women in STEM feel supported and have a sense of belonging throughout Emerson; provide a platform to highlight women in STEM as role models across Emerson

Emerson’s WiS program enables us to facilitate community outreach throughout our global offices and places of business. For example, the local WiS chapter in our Sidney, Ohio, location includes more than 100 members comprised not only of Sidney branch employees, but also extending out into other local manufacturing and engineering-related companies.

Ongoing commitment to STEM education, activities and events

Even though the past two years have made it difficult to plan and host in-person, STEM-related events, Emerson has continued to develop a series of educational webinars and promotional activities focused on professional development, social networking and STEM outreach to schools and universities. These activities include:

  • Sponsoring a cardboard boat race during the Summer Olympics
  • Celebrating Pi Day with pi-inspired games and the distribution of moon pies
  • Hosting a WiS online trivia event
  • Conducting educational webinars with prominent female executives and keynote speakers

Collectively, these achievements, educational events and promotional activities represent our ongoing commitment to furthering STEM careers and related disciplines — within Emerson and the global workforce. Emerson’s ongoing WiS efforts are having a direct impact on our business, transforming our culture and infusing it with fresh perspectives and insights that make us a more well-rounded and successful organization.

 

Refrigeration Basics: Addressing the HVACR Technician Shortage

         Don Gillis | Lead Technical Trainer

          Emerson’s Educational Services

Welcome to the fifth and final installment in our blog series intended to help not just beginning service technicians, but anyone who wants to learn more about the basics of refrigeration. In this blog, I explain what we at Emerson and others are doing about the growing shortage of skilled, qualified and certified HVACR technicians in the industry. For this series, we’ve also created companion videos about each topic that you can cross-reference while accessing other related information at Education.Emerson.com.

Nearly 40 percent of the jobs available in the HVACR industry are unfilled. That’s about 80,000 good-paying positions for technicians who can install, maintain and repair the critical refrigeration equipment upon which our customers depend. At the same time, our industry loses experienced technicians as aging workers retire and also as the result of normal attrition every year. If we do not hire and train new technicians, our industry could potentially face a deficit of 100,000 workers within the next five years.[i]

That’s one of the reasons I’ve written this series of blogs about refrigeration basics. With the help of others at Emerson, I’ve also created a related set of videos to explain what refrigeration technicians do — and what they must know to be successful in our business. We need more skilled, qualified and certified HVACR technicians. So we’re promoting our educational services, which include instructor-led and online courses.

Emerson also partners with industry organizations and leaders to create learning opportunities through events such as World Refrigeration Day. To mark that day in June, we shared a webinar, Exploring Cool Careers and Emerging Opportunities in HVACR, which showed how refrigeration technicians have a high earning potential and work with advanced technologies and modern tools. You can watch the webinar on-demand.

Young people should consider a career in HVCAR because they can:[ii]

  • Make an impact — Refrigeration technicians implement new environmentally friendly solutions that will play an integral role in making the world a better place to live.
  • Work with cutting-edge tools and technologies — Modern refrigeration and air conditioning applications utilize advanced controls, software and remote diagnostics capabilities.
  • Achieve job security — With little competition for available jobs, HVACR professionals are virtually guaranteed employment and will enter into a field with both long-term security and growth potential.
  • Earn while they learn — HVACR technicians can earn a competitive wage with a two-year vocational certification and have the option to augment the certification process with on-the-job training in apprenticeship programs.

At Emerson, we are committed to recruiting the next generation of HVACR technicians. Our company is addressing the technician gap in three ways by:

  1. Offering courses for upcoming technicians so that they can expand their knowledge of HVACR fundamentals
  2. Recruiting the next generation of HVACR technicians by providing real-life experiences through co-ops and internships
  3. Partnering with industry leaders so that we can brainstorm ways to bridge this gap

The reality is that there’s an abundance of lucrative opportunities for young people who want a long-term career path without the time commitment and cost of a four-year college education. That’s why I’m really excited about the future of the refrigeration industry. Indeed, jobs and training are available to enable people to acquire the necessary refrigeration skills. Emerson is helping in that regard, too. If you’re interested, let’s talk.

 

Read “Reversing the Trend: Recruiting the Next Generation of HVACR Professionals ” to discover how Emerson is working to make refrigeration technician careers ‘cool’ again.

 

 

 

[i] Rajan Rajendran, “Become a “Cooling Champion” for World Refrigeration Day 2021,” June 26, 2021, Emerson Climate Conversations, https://emersonclimateconversations.com/2021/06/26/become-a-cooling-champion-for-world-refrigeration-day-2021 (accessed July 20, 2021).

 

[ii] Rajan Rajendran, “Reversing the Trend: Recruiting the Next Generation of HVACR Professionals,” E360 Outlook, June 2021, https://climate.emerson.com/documents/e360-article-reversing-trend-en-us-7598000.pdf (accessed July 20, 2021).

 

 

Refrigeration Basics: Understanding the Refrigeration Cycle

         Don Gillis | Lead Technical Trainer

          Emerson’s Educational Services

Welcome to the fourth installment in our series of blogs intended to help not just beginning service technicians, but anyone who wants to learn more about the basics of refrigeration. In this blog, I explain the nuances of vapor injection along with the full refrigeration cycle. For this blog series, we have also created companion videos about each topic that you can cross-reference while accessing related information at Education.Emerson.com.

Comparing Refrigeration to a Baseball Diamond

The refrigeration cycle requires four main components. No matter how small or how large a cooling system might be, its design will include a compressor, a condenser, a metering device and an evaporator.

When I teach new technicians, I often compare the refrigeration cycle to the layout of the field for the game of baseball. I’ve found this analogy makes refrigeration equipment and processes easier for them to understand.

 

 

 

 

 

 

 

 

 

 

 

In my example, a compressor is located at home plate at the bottom of the baseball diamond (shown above). In a refrigeration or cooling system, compression is the first step:

  • Refrigerant enters as a low-pressure (LP), low-temperature (LT) superheated vapor and exits the compressor as a high-pressure (HP), high-temperature (HT) vapor.
  • The compressor mechanically compresses the refrigerant gas.
  • Under pressure, the refrigerant volume is reduced and the temperature is raised.

The second step involves a condenser, located at first base on the right side of the baseball diamond:

  • Hot, pressurized refrigerant gas arrives from the compressor into the condenser, which is designed to reject heat by lowering or returning the temperature of the refrigerant to its condensing temperature.
  • As it rejects heat, the condenser converts the vapor to a sub-cooled liquid.
  • In most condensers, the refrigerant gas enters at the top of the equipment and leaves at the bottom because the refrigerant in a liquid state is much heavier than the weight of refrigerant in a gas state.

In the third step, a metering device located at second base at the top of the baseball diamond regulates the amount of refrigerant released into the evaporator in response to the cooling load and causes a pressure drop.

The metering device also:

  • Measures the superheat at the evaporator outlet
  • Maintains a constant temperature by raising or lowering the amount of refrigerant flowing into the evaporator

At the fourth step, cold liquid refrigerant mixes with vapor causing the saturation temperature as it boils off or vaporizes in the evaporator, located at third base, on the left side of the baseball diamond:

  • The process allows the refrigerant to absorb heat through a series of metal coils.
  • The low-pressure superheated vapor refrigerant gas then returns to the compressor to continue the refrigeration process.

Here is the value of comparing the refrigeration process to a baseball diamond: If I draw a vertical line from home plate up to second base, everything in the system on the right side of that line is under high pressure; everything on the left side of that line is low pressure.

Likewise, if I draw a horizontal line from first base to third base, the refrigerant above the line is in a liquid state; below the line, the refrigerant is a vapor, regardless of whether it is under high or low pressure.

Liquid Injection Cools Compressor and Increases Capacity

A compressor is designed to operate at very high temperatures, so a liquid injection method has been developed to cool the compressor internally. How this works can be confusing; refrigerant is injected in a vapor state, not in a liquid state.

When necessary, liquid injection cools a compressor to enable it to run reliably under difficult high compression ratio conditions normally seen on low-temperature freezer applications.

  • Refrigerant is piped from the system liquid line, through an injector valve to the compressor; in scroll compressors, the refrigerant is injected directly into the scroll elements.
  • Without this cooling, the compression elements can get too hot and the oil breaks down, leading to compressor failures.

Another approach called enhanced vapor injection (EVI) increases refrigeration capacity and, in turn, the efficiency of the system:

  • A heat exchanger is utilized to provide subcooling to the refrigerant before it enters the evaporator.
  • A small amount of refrigerant is evaporated and superheated above its boiling point.
  • This superheated refrigerant is then injected mid-cycle into the scroll compressor and compressed to discharge pressure.

The diagram below shows how enhanced vapor injection (EVI) increases the efficiency of the system.

 

 

 

 

 

 

 

 

 

EVI increases the compression ratio and, in the process, boosts capacity for the refrigeration system. The greatest gains can be achieved during the summer months and other periods when warm ambient temperatures require more cooling.

View our new video series to learn more about the refrigeration cycle. For a deeper dive into all of our training content and access to our other educational resources, visit Education.Emerson.com.

Refrigeration Basics: A Look at Each Step of the Refrigeration Cycle

         Don Gillis | Lead Technical Trainer

          Emerson’s Educational Services

Welcome to the third installment in our blog series intended to help not just beginning service technicians, but anyone who wants to learn more about the basics of refrigeration. In this blog, I introduce some of a refrigerant system’s many basic components, explain what each is designed to do and discuss how they work together. For this blog series, we have also created companion videos that you can cross-reference while accessing other related information at Education.Emerson.com.

Step one: compression

In a compressor-based refrigeration or cooling system, refrigerant enters the compressor as a low-pressure, low-temperature superheated vapor and exits the compressor as a high-pressure, high-temperature superheated vapor. The compressor — which could be centrifugal, reciprocating, rotary, scroll or screw design — mechanically compresses the refrigerant gas. Under pressure, the refrigerant volume reduces, and the temperature rises.

The relationship between pressure and temperature is critical to how efficiently and effectively the system can achieve and maintain its intended setpoint.

Step two: condensing

This second step in the refrigeration process is necessary to convert the vapor to a liquid. As the compressor releases hot, pressurized refrigerant gas into a condenser, it rejects the heat by lowering or returning the temperature of the refrigerant back to its condensing temperature. Condensers utilize three primary cooling methods:

  • Air-cooled — often found in small systems and residential applications; air flows naturally or is forced by a fan over metal (typically copper or aluminum) coils, which carry the heated refrigerant
  • Water-cooled — utilized in commercial systems, large plants and when operating in higher ambient temperatures; cool water replaces natural or forced airflow around the coils carrying the heated refrigerant
  • Evaporative — combines air and water cooling in large-scale facilities such as those for making ice

In most condensers, the refrigerant gas enters at the top of the equipment and leaves at the bottom because the refrigerant in a liquid state is much heavier than the weight of refrigerant in a gas state.

Step three: thermal expansion valve (TXV)

In the third step, the liquid refrigerant is cooled further when pressure is suddenly decreased by the TXV. The valve regulates the amount of refrigerant released into the evaporator in response to the cooling load.

It also measures the superheat leaving the evaporator outlet and maintains a constant temperature by raising or lowering the amount of refrigerant flowing into the evaporator. A precisely controlled flow maximizes the efficiency of the evaporator and ensures that we only have vapor returning to the compressor.

The TXV has multiple ports with bulbs that read:

  • P1 — the temperature as refrigerant leaves the evaporator
  • P2 — the pressure inside the evaporator
  • P3 — the closing force to control superheat flow into the evaporator (if adjustable)
  • P4 — the opening force, liquid line pressure

Step four: cooling in the evaporator

The evaporator is the part of a refrigeration system where the actual cooling takes place. In this fourth step, sub-cooled liquid refrigerant begins boiling off or vaporizes in a process that allows the refrigerant to absorb heat through a series of metal coils. The refrigerant is saturated through this process and this low-pressure, superheated vapor and then returns to the compressor to continue the refrigeration process all over.

What does a suction line accumulator do?

The last system component you should be aware of is the suction line accumulator. This device protects the compressor from a sudden surge of liquid refrigerant and oil that could enter the compressor. Compressors are designed to compress refrigerant in its vapor state. If liquid refrigerant gets into the compressor, we refer to that as “liquid floodback,” resulting in a condition called slugging that can reduce efficiency and cause premature equipment failure.

View our new video series to learn more about the refrigeration cycle. For a deeper dive into all our training content and to access our other educational resources, please visit Education.Emerson.com.

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